The present invention relates to a module for a high- and medium-voltage electric station, i.e. for applications with operating voltages above 1000 V; more particularly, the present invention relates to a module for an electric station which distinguishes itself with respect to known types of device due to the simplicity, compactness and modularity of its constructive structure and is accordingly extremely flexible in application and significantly convenient from an economic point of view.
It is known from the art that air-insulated high- and medium-voltage electric stations use a system of busbars, each of which is appropriately connected to a main electric power supply line and to a power transformer; the substation is furthermore provided with a series of primary components, for example disconnectors, circuit breakers, instrument transformers, et cetera, and secondary components, such as busbar protections, maximum-current protections, and control systems.
According to a conventional embodiment, the stations are produced by assembling the various components directly on site, generally arranging them on mutually separate supports. This solution entails a considerable use of labor at the installation site for assembly, adjustment and electrical testing. This solution furthermore entails the use of considerable space, which leads to an increase in the costs required for the purchase of land and, in view of the large number of foundations and supports required, to an increase in construction difficulties, especially when the space available is limited and/or the preparation of the foundations is rendered difficult by the very nature of the soil; furthermore, the environmental impact is considerably negative. If one wishes to avoid performing electrical testing at the installation site, it is necessary to oversize the insulation distances for safety reasons and therefore oversize accordingly the entire station.
Constructive solutions are also known which use apparatuses which integrate multiple electrical functions in a single component. An example of this type is described in European patent application no. 0774814. Another known type of solution associates with each interruption pole a two-blade disconnector and performs the disconnection maneuvers by turning said pole; conventional instrument transformers can furthermore be optionally integrated in the structure of the pole. Although these solutions adequately achieve the required electrical performance and allow a reduction of the required supports with respect to more conventional solutions, they still require assembly directly at the installation site, with the same drawbacks noted above. Furthermore, the interruption poles are generally constituted by shaft-like insulators which are constituted by two parts: a first one, commonly known as supporting insulator, inside which the means for actuating the contacts of the circuit breaker are arranged, and a second one, which is arranged in the upper part of the pole and contains the interruption elements. Accordingly, visual impact is still considerable, also in view of the fact that the constructive dimensions increase as the voltage involved increases; any use of conventional instrument transformers inside the pole contributes to an increase in space occupation and visual impact.
Another considerable drawback of known types of solution is the fact that the electrical maneuvers are generally performed by means of mechanical actuation devices which have a large number of components and require long and complicated adjustments; furthermore, the movement of the moving parts, particularly of the movable contacts, cannot be changed by the user but is set during design. This lack of control furthermore requires the presence of damping elements or shock absorbers in order to dissipate the residual kinetic energy at the end of the maneuver and avoid uncontrolled impacts. Furthermore, due to the large number of components, frequent maintenance interventions are required in order to maintain nominal behavior and therefore ensure repeatability of maneuvers.
Alternatively, actuation devices of the hydraulic type are used which can partly obviate these drawbacks but have inherent limitations linked to the presence of fluids, especially as a consequence of their temperature-sensitivity.
The aim of the present invention is to provide a module for a high- and medium-voltage electric station whose structure allows to perform assembly and technical testing directly at the factory, thus allowing transport to the site in a configuration which is already preset for the operative placement.
Within the scope of this aim, an object of the present invention is to provide a module for a high- and medium-voltage electric station which has a multifunctional structure in which electrical maneuvers can be performed simply and effectively, allowing accuracy and repeatability of said maneuvers, and a significant reduction in the space required with respect to the state of the art.
Another object of the present invention is to provide a module for a high- and medium-voltage electric station which has a compact and modular structure which allows to reduce environmental visual impact and installation costs.
A further object of the present invention is to provide a module for a high- and medium-voltage electric station which is highly reliable, relatively easy to manufacture and at competitive costs.
This aim, these objects and others which will become apparent hereinafter are achieved by a module for a high- and medium-voltage electric station, comprising: a supporting frame, which has a fixed part and a movable part; first actuation means, which are suitable to move said movable part; a first and a second sets of three insulating posts, arranged on the fixed part along two corresponding rows; first and second disconnection contacts being respectively associated with the insulating posts of said first and second sets and being electrically connectable, in input and in output with respect to the module, to corresponding electric terminals; characterized in that it comprises a set of three multifunctional interruption assemblies, each of which comprises:
a supporting insulator, arranged on said movable part and connected in an elbow-shaped configuration to a containment insulator, said containment insulator containing at least one interruption unit which has a fixed contact and a movable contact which is operatively connected to second actuation means;
third and fourth disconnection contacts, which are electrically connected to said interruption unit and are connected, in a disconnectable way, to said first and second disconnection contacts, respectively; the actuation of said movable part producing a movement of the multifunctional assemblies between a first position, in which the third and fourth disconnection contacts are respectively connected to the corresponding first and second disconnection contacts, and a second position, in which they are disconnected therefrom; and in that said first and/or second actuation means comprise a motor with position control.
In this manner, one obtains an extremely compact module in which electrical maneuvers are performed very simply and effectively, at the same time ensuring their accuracy and repeatability. Furthermore, the module according to the invention has a constructive structure which makes it directly transportable to the installation site in an already preassembled configuration, with an installation and supporting frame layout which considerably reduces the space required and at the same time reduces the number of foundations and supports required and also reduces environmental impact.